12 United States sites
16 to 70 Years
– Male and non-pregnant female patients 16-70 years of age (inclusive)
– Confirmed diagnosis of sickle cell disease by hemoglobin electrophoresis or
high-performance liquid chromatography (HPLC) [performed locally]. All sickle cell
disease genotypes are eligible.
– Experienced at least 1 VOC within the preceding 12 months prior to Screening, as
determined by medical history.
– If receiving HU/HC or erythropoietin stimulating agent, must have been receiving the
drug for at least 6 months prior to Screening
– Hemoglobin ≥4.0 g/dL. Absolute neutrophil count ≥1.0 x 109/L and platelet count ≥75 x
– Adequate renal and hepatic function as defined:
– GFR ≥45 mL/min/1.73 m2 calculated by CKD-EPI
– ALT ≤3 x ULN
– Direct (conjugated) bilirubin ≤2 x ULN
– ECOG performance status ≤2
– Written informed consent (or assent/ parental consent for minor subjects) prior to any
– History of stem cell transplant.
– Acute VOC ending 7 days prior to first dosing
– Ongoing hospitalization prior to Screening
– Received blood products within 30 days to first dosing
– Participating in a chronic transfusion program (pre-planned series of transfusions for
– History of severe hypersensitivity reactions to other monoclonal antibodies
– Received a monoclonal antibody or immunoglobulin -based agent within 1 year of
Screening, or has documented immunogenicity to a prior biologic.
– Received active treatment on another investigational trial within 30 days (or 5
half-lives of that agent, whichever is greater) prior to Screening
– Significant active infection or immune deficiency (including chronic use of
– Resting QTcF ≥470 msec at pretreatment (baseline) or other cardiac or cardiac